Melt butter in a saucepan over low heat. Add marshmallows and stir until completely melted.

Cook over low heat 3 minutes longer, stirring constantly.

Remove from heat. Stir in peanut butter and mix thoroughly. Stir in cereal until well coated.

Using a buttered spatula or waxed paper, press mixture evenly into a buttered 9 x 13 inch baking pan.

Cut into 2 inch squares when cool. This recipe serves 18.